Bloomberg View just published a great Nathan Myrhvold piece on our human tendency toward complacency in the face of threats that aren’t actively killing us.

One could recount many such examples, but people’s eyes tend to glaze over when you talk about something that last occurred in 1783, much less 934. Surely things are different now, they say. The unfortunate truth is quite the opposite — a millennium ago was yesterday as far as the Earth is concerned, and the relevant phenomena operate as vigorously as ever. Proud as we are of the many technological achievements of modern society, we are actually more vulnerable than ever because we live more densely, within a complex and sometimes fragile web of buildings, roads, bridges and the like.

There is an obvious investing parallel here, as investors in Iceland, Japan and Greece could attest to. An unusual, but mortal, threat is worth your attention. If you are willing to insure a $40,000 car but have no risk management plan for a million dollar portfolio, the time for a strategy session is now.